Roanoke Series

The Roanoke series consists of poorly drained, nearly level soils on stream terraces. These soils formed in alluvial sediment. A seasonal high water table is at or near the surface. In a typical profile, the surface layer is dominantly dark grayish-brown silt loam about 9 inches thick. Beneath the surface layer is a gray subsoil about 33 inches thick. The upper part of the subsoil is dominantly very firm clay mottled with very dark gray and brownish yellow. The lower part is firm silty clay loam mottled with brownish yellow and dark gray. Below the subsoil and extending to a depth of about 66 inches is gray loamy fine sand and loamy sand mottled with light gray and brownish yellow. Underlying this material and extending to a depth of about 74 inches is white sand mottled with olive yellow. Natural fertility and available water capacity are medium, and the content of organic matter is low. Permeability is slow, and shrink-swell potential is high. In areas that have not received lime, reaction is very strongly acid. The Roanoke soils in Pitt County are of only minor importance for farming. Most of the acreage is in forest, and the rest is chiefly in cultivated crops or pasture. The seasonal high water table, frequent flooding for brief periods, and slow permeability are major limitations to the use of these soils for farming and for other purposes. In areas that are farmed, crops respond well to recommended applications of fertilizer and lime. Representative profile of Roanoke silt loam, 3 miles west of Grimesland on U.S. Highway No. 264, 0.4 miles north on State Road No. 1762, 30 feet east of road and 100 feet north of a wooded area:

Ap – 0 to 7 inches, dark grayish-brown (10YR 4/2) silt loam; weak, medium, granular structure; very friable; many small roots; medium acid; abrupt, smooth boundary. A2 – 7 to 9 inches, gray (10YR 5/1) very fine sandy loam; many fine distinct, brownish-yellow mottles; weak, medium, granular structure; friable; many small roots; few small root channels; very strongly acid; abrupt, smooth boundary. B1tg – 9 to 12 inches, gray (10YR 6/1) clay loam; few, fine, distinct, brownish-yellow mottles; weak, medium, subangular blocky structure; firm, sticky and plastic; few medium roots and root channels; some dark grayish-brown colors in root channels; few thin clay films on faces of peds; very strongly acid; abrupt, smooth boundary. B21tg-12 to 26 inches, gray (10YR 6/1) clay, few, coarse, distinct, very dark gray (10YR 3/1) mottles and few, fine, distinct, brownish-yellow mottles; weak, medium, angular blocky structure; very firm, very sticky and very plastic; few medium roots and root channels; thin, patchy clay films on faces of peds; very strongly acid, gradual, wavy boundary. B22tg – 26 to 36 inches, gray (10YR 5/1) clay; few, medium, distinct, brownish-yellow (10YR 6/6) mottles; weak, medium, angular blocky structure; very firm, very sticky and very plastic; few, thin, patchy clay films on faces of peds; very strongly acid; gradual, wavy boundary. B3tg – 36 to 42 inches, gray (10YR 6/1) silty clay loam; few, fine, distinct, brownish-yellow and dark-gray mottles; weak, medium, angular blocky structure; firm, sticky and plastic; few, thin, patchy clay films on faces of peds; very strongly acid; gradual, wavy boundary. IIC1g – 42 to 54 inches, gray (10YR 6/1) loamy fine sand; few, fine, faint, light-gray mottles; single grain; very friable; very strongly acid; gradual, wavy boundary. IIC2g – 54 to 66 inches, gray (10YR 6/1) loamy sand; few, fine, distinct, brownish-yellow mottles; single grain; very friable; very strongly acid; gradual, wavy boundary. IIC3g – 66 to 74 inches, white (N 8/0) sand; few fine, distinct, olive-yellow mottles; single grain; loose; very strongly acid.

Thickness of the solum is 45 inches or less. Thickness of the A horizon is 5 to 20 inches. The Ap or A1 horizon is dark gray to dark grayish brown, and the A2 horizon is commonly gray. Texture of the B horizon is silty clay loam, clay loam, or clay, but it is dominantly clay. The B horizon is commonly mottled with brownish yellow, dark gray, and very dark gray. The C horizon is gray to white with loamy fine sand to sand.

Roanoke silt loam (Ro) – This is a poorly drained soil on broad flats in slight depressions. It is on stream terraces, where it occurs in areas of irregular shape. The areas range from 3 to more than 100 acres in size. Slopes are 0 to 1 percent. The surface layer is dominantly dark grayish- brown silt loam about 9 inches thick. The subsoil is gray and is about 33 inches thick. The upper part of the subsoil is dominantly very firm clay mottled with very dark gray and brownish yellow. The lower part is firm silty clay loam mottled with brownish yellow and dark gray. The underlying material is gray to white loamy fine sand to coarse sand. Included with this soil in mapping were a few areas of soils that have a similar profile but that have a surface layer of very fine sandy loam or loam. Also included were small areas of Altavista, Bibb, and Cape Fear soils. Infiltration is moderate. Runoff is slow or ponded. This soil is fairly easy to keep in good tilth, but it can be satisfactorily worked only within a fairly narrow range of moisture content. Most of the acreage is in forest, and the rest is chiefly in cultivated crops or pasture. Flooding frequently occurs for brief periods, and wetness is a very severe limitation. A system of surface drains is needed for most uses. If properly drained, this soil is suited to a few of the locally grown crops. Areas that are farmed are used mainly for corn, soybeans, and pasture. Capability unit IVw-2; woodland suitability group 2w9.